Design And Research Of The Temperature Distribution Curve Of The Soldering Pen

A new kind of soldering tool that’s name is soldering pen is designed, in view of the facts that solder joints’reliability quality is not enough because the separate of solder and heating source. The control of temperature distribution and liquid solder flow in soldering pen’s melting chamber are two important factors that affect the welding quality of soldering pen. The paper is mainly about the design and research of temperature distribution for soldering pen’s melting chamber. With analysis and summary of temperature distribution requires about different kinds of welding, a temperature distribution curve for soldering pen’s melting chamber is put forward. It can be divided into three areas. The first area’s height is4.5-6cm and temperature range is about120-217℃. The second area’s height is1-4.5cm and temperature range is approximately217-400℃. The third area’s height is0-1cm and temperature range is about250-350℃. A fuzzy self-tuning PID algorithm is designed for the temperature control of this soldering pen. Simulink and fuzzy logic toolbox in Matlab are used to Simulate for this algorithm.The simulation results show that the fuzzy self-tuning PID controller can satisfy the requirements of short setting time, small overshoots and small steady-state error. It can achieve requirements of soldering pen’s temperature well. For the soldering pen designed, the temperature distribution curve obtained by detecting the temperature of the different height points and its overall trend is consistent compared to the temperature distribution curve of theoretical design.But there are different aspects. The temperature in the first area is substantially closest. The temperature in the second area is higher50℃than the design temperature and the te mperature in the third area is lower25℃than the design temperature because the quantity of heat transferred is too large. The temperature distribution curve designed for soldering pen can reflects the temperature distribution requirements of melting chamber. And it is the theoretical foundation for the subsequent welding pen liquid solder flow control and improve the quality of solder joints.